In the field of medicine, many image recording techniques are known in which image records are recorded, taking into account different parameters so that a particular item of information about a target volume can be determined therefrom and can be displayed.
One example of this is magnetic resonance perfusion records, with the aid of which the perfusion of a particular tissue region, for example, is intended to be measured. In the process, a contrast agent is injected and, for example, observations are made regarding the speed at which this contrast agent moves into the tissue and out of the tissue. Since the contrast agent is transported by the blood, a statement regarding the perfusion is possible. Such perfusion image records are often recorded once at rest and once under stress, whereupon the results of the two records are compared. Defects can easily be recognized by comparing these records.
Another known example of such records is so-called viability records. Here, the fact that the contrast agent accumulates in dead tissue is used so that diseased tissue can be distinguished from healthy tissue. This in turn is of interest to various target volumes, in particular tissue regions.
In order to be able to obtain the desired information from such image records, parameters are used which clearly highlight the peculiarities of the target volume (and the surroundings of the target volume) which contain this information; this often occurs to the detriment of the contrast or the resolution of natural anatomical features. By way of example, the perfusion and viability records are recorded such that the contrast agent wash-in and later accumulation can be recognized particularly well in the images obtained.
However, in this, case it important to observe only the target volume which is actually of interest. For example, if the target volume is the myocardium, with ischemic or necrotic tissue intended to be found, then only data from the myocardium can be taken into account for determining the information. For this reason, it is normal practice to segment the target volume in the records; this usually has to be carried out manually due to the lack of contrast of the anatomical boundaries, and is very error-prone. This in turn can lead to critical false information which incorrectly describes the state of health of a patient.
It is often the case that, within the scope of more extensive or precise examinations, a plurality of image records of a target volume or neighboring target volumes are actually recorded. By way of example, if the heart of a patient is intended to be examined for ischemia, both so-called function image records and perfusion or viability records are to be recorded in a magnetic resonance examination. The target volume must subsequently be segmented in each of these image records, requiring great effort.